Equipment Platforms and Second Means of Egress

[glzath]

An equipment platform and second means of egress question. IBC 2009 basis.

We have an industrial project that would fall under the F-2, Low Hazard occupancy classification. IIB construction. No sprinkler system.

The 80 foot tall building will house large pieces of equipment related to the pollution control at power generation facilities. There are no permanently, occupied spaces such as control rooms, offices, breakrooms, restrooms, etc. You just have the equipment which is attended to periodically.

Around the equipment you have a series of platforms, mostly metal grating with a few concrete slabs. These platforms are used solely to maintain the equipment. Access to these maintenance platforms is by a single, unenclosed, 36” wide scissors stair with complaint guards, handrails and landings. Travel distance is within the 300 feet allowed. We are also supplying fire escape ladders (NFPA 101 7.9.2.1(3)) as a second means of egress from platforms larger than 300 SF.

The issue we are running into is that the aggregate area of all the equipment platforms is greater than two-thirds of the floor area of the building. (505.5.1) Are they now considered floors/stories? I’m having a difficult time wrapping my head around these unoccupied (by IBC definition) equipment platforms now having to be classified as something else.

The other question is we were just supplying a single stair as an access to these platforms. Would there now be a second stair requirement?

Thanks in advance.

 

[cda]

Is it one big room, or multiple rooms?

 

[glzath]

One big room.

 

[north star]

: - :

glzath,

Have you calculated a possible Area Increase, so that your total

platform areas do not exceed the 2/3's amount of floor area

[ RE: Section 506.4, `09 IBC ] ?

: - :

 

[cda]

not a building code expert, but I think the answer to your question is yes they are a story and cannot be considered a mezzanine, since you do not meet all of 505. over the 2/3 max rule

cut them back to 2/3 max. ???

 

[north star]

: - : - :

glzath,

In reading Section 503.1.1 - Special industrial occupancies,

`09 IBC, it appears as though you do not have a limited floor

area amount. "Buildings and structures designed to house special

industrial processes that require large areas and unusual building

heights to accommodate craneways or special machinery and

equipment, including, among others, rolling mills; structural metal

fabrication shops and foundries; or the production and distribution

of electric, gas or steam power, shall be exempt from the building

height and area limitations of Table 503."

Sounds as though you do not have to worry about the 2/3's

Floor Area amount.

Also, I don't think that a scissor stair would be considered a

compliant stair/ MOE [ RE: Section 1015.6.1, # 5, `09 IBC ].

: - : - :

 

[ICE]

If the platforms are mounted to the equipment, I would say that they are part of the equipment.

 

[cda]

: - : - :glzath,

In reading Section 503.1.1 - Special industrial occupancies, `09 IBC,

it appears as though you do not have a limited floor area amount.

"Buildings and structures designed to house special industrial

processes that require large areas and unusual buildingheights to

accommodate craneways or special machinery and equipment,

including, among others, rolling mills; structural metal fabrication

shops and foundries; or the production and distribution of electric,

gas or steam power, shall be exempt from the building height and

area limitations of Table 503."

Sounds as though you do not have to worry about the 2/3's

floor AREA amount.



: - : - :

but if you read 505.5 says almost the same thing, if the platform can be kept below 2/3

that and the building proposed is able to accomodate the equipment

 

[north star]

+ = +

"but if you read 505.5 says almost the same thing, if the platform can be kept below 2/3that and the building proposed is able to accomodate the equipment"

Agreed !......2/3's Floor Area max !And you said that you weren't a bldg. codes expert!

+ = +

 

[glzath]

Thanks all for your input. I kind of figured the platforms needed to be held under the 2/3rds ... just wanted to see if there was something I may have missed.

In the past, I have been able to get some of the platforms equipment-mounted to help in the 2/3rds calc, but unfortunately most of the other platforms, due to their layout need to be supported off the building steel.

Well, we are in the early schematic/concept phase so I'll just put the screws to my process and structural folks and give them a square footage to stay under.

 

[north star]

: - :

glzath,

What about your [ possible ] 2nd Means of Egress from your

platforms ?.......Is this still one of your questions ?

: - :

 

[glzath]

If we can keep the aggregate equipment platform area to under 2/3rds, they will remain as "unoccupied", per the IBC definition. The stairs would be access for the platforms. The the secondary ladder egress on any of the larger platforms is for added safety factor per the clients request. Now, if we need to turn one or more of the platforms into a floor, we will add a second stair up to that level.

One of Engineers has already been over this morning rolling his eyes at my request. Oh well, trim the fat or add in the cost of a second stair.

 

[north star]

: - :

glzath,

Thanks for the input / update on your application!

My secondary question has to do with the "scissor

type stair" that you mentioned in your OP......Do

your platforms have a fixed type of stair / ladder

[ MOE ], rather than a non-fixed / non-permanent

type of egress ?

: - :

 

[glzath]

Sorry north, my bad. They will be a fixed "half-turn" or "U" stair. Not a scissors stair. I can see how you may have misinterpreted them to be a mobile scissors-type lift.

 

[north star]

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glzath,

Thanks for the update !

Also, ...Welcome to The Building Codes Forum!

Please come back often and tell others !

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